The present invention relates generally to portable electronic devices such as smartphones or other cell phones, and more specifically to cases for controlling the amount of RF signal reaching or leaving such devices.
The recent proliferation of smartphone technology and supporting applications has increased their functionality and usefulness. This has spawned an uncharted frontier of opportunities such as applications, accessories, and social networking Smartphones are rapidly becoming an indispensable electronic appendage in everyday life in most societies globally.
Recent scientific studies have concluded that radiation associated with cell phones is potentially carcinogenic. Other scientific research by the World Health Organization has shown that cell phones emit high levels of electromagnetic radiation when the device is searching for a cell tower or when in an area with a weak signal. Findings in the same research recommend that users not carry cell phones in their pockets.
Radiation exposure is often quantified by the specific absorption rate (“SAR”), which is a measure of the rate at which energy is absorbed by the body when exposed to a radio frequency (RF) electromagnetic field (frequencies between 100 kHz and 10 GHz). The U.S. Federal Communications Commission (“FCC”) specifies that phones have a SAR level at or below 1.6 watts per kilogram (W/kg) taken over a volume containing a mass of 1 gram of tissue. Other jurisdictions have similar requirements.
Inherent with this technological boom in cell phones and related apps are the issues of both end user and network security. Those with malicious intent are rapidly finding more and more ways to circumvent existing security measures and exploit system vulnerabilities. There exist malware apps that can, for example, expose critical confidential information and make it available to unauthorized entities, and it is easy and all-to-common for users to inadvertently end up with this malware installed on their smartphones.
Another issue is location privacy; even when a cell phone has its GPS feature disabled, that phone is still being tracked as it transmits from cell tower to cell tower in transit. This happens whether the cell phone owner wants it to or not. While some see this as part of the trade-off for advanced technology, others want to decide whether or not to have their phone tracked.
Separate from privacy and security considerations is the issue of distracted driving. For example, the California Highway Patrol statistics show a year-by-year increase in the number of citations issued for driving while using a cell phone without the aid of a hands-free device. Equally on the rise are the numbers of fatal car accidents and injury accidents due to drivers being distracted by using a cell phone or texting.
In short, embodiments of the present invention provide a shield having a compartment sized and configured to receive a portable electronic device (or simply “portable device” or “device” where clear from the context) that can be configured by the user to operate in either a blocking mode or a normal-use mode. This is effected by providing relatively movable elements of the shield with shielding material. By engaging and disengaging the shield elements, the portions of shielding material on the shield elements are engaged and disengaged.
In the blocking mode, elements of the shield are engaged so that the shielding material surrounds the device and prevents a significant portion of RF signals emitted by the device from leaving the shield, and further prevents a significant portion of RF signals impinging on the shield from outside from reaching the device. In the normal-use mode, elements of the shield are disengaged so the RF signals can enter and leave the shield.
The term “shielding material” as used in this application is intended to mean material whose composition and or dimensions cause it to prevent a significant portion of RF signals incident thereon from penetrating the material. While the ideal would be 100%, in this context, a “significant portion” is intended to mean at least 75%, preferably at least 85%, and most preferably at least 95%. The shielding material will typically be an electrically conductive material, but certain plastics such as ultra-high-molecular-weight (“UHMW”) plastics can be used in some applications. The UHMW material can be filled with conductive material such as carbon, but need not assuming it is sufficiently thick. Such a plastic material could be used instead of, or in conjunction with, conductive materials.
The term “RF signal” as used in this application is intended to mean electromagnetic signals in the frequency range(s) commonly used by portable electronic devices for communication. Typical mobile phones and smartphones operate in frequency bands in the ultra-high frequency (“UHF”) range, which the International Telecommunication Union (“ITU”) defines as 300 MHz to 3 GHz.
In some embodiments of the present invention, the shield includes an additional compartment sized and configured to receive a portable charger for charging the portable device. The additional compartment can further include a portion sized and configured to receive one or more interchangeable power adapters to allow the shield to be used with different makes and models of device. These adapters are preferably formed so that when connected to a charger cord, the plug that engages the portable device is at a right angle to the cord.
In an aspect of the invention, a shield for a portable electronic device comprises a housing having an open-ended container element and a closure element. The container element is formed with an opening sized to allow passage of the device through the opening, and the closure element has respective engaged and disengaged positions relative to the container element for selective engagement with the container element. The shield further comprises first shielding material carried by the container element and second shielding material carried by the closure element. The first shielding material partially surrounds portions of the device that have been inserted through the opening in the container element.
When the closure element is in its engaged position, the container element and the closure element provide a compartment for the device, and the first shielding material and the second shielding material together substantially surround the device. This substantially prevents RF signals emitted by the device from leaving the shield, and further substantially prevents RF signals impinging on the shield from outside from reaching the device. When the closure element is in its disengaged position, the first shielding material and the second shielding material leave a gap. This allows RF signals emitted by the device to leave the shield, and further allows RF signals impinging on the shield from outside to reach the device.
The housing can further comprise an additional closure element having respective engaged and disengaged positions relative to the container element for selective engagement with the container element, and when the first-mentioned closure element is in its disengaged position, the additional closure element can be moved to its engaged position to prevent the device from falling out of the housing.
In a particular implementation, the container element and closure element are provided by a pouch with a folding flap, and the housing further comprises a rigid tray that includes a plate and an upstanding frame whose inner dimensions define the opening in the container element.
In another particular implementation, the housing comprises an additional open-ended container element formed with an opening sized to allow passage of a charger through the opening. The shield can be configured so that when the closure element is in its engaged position, the closure element also engages with the additional container portion so that the additional container portion and the closure element provide a compartment for the charger.
The additional container element can be provided by a pouch, and the housing can further comprise a charger tray sized for insertion in the pouch's opening wherein the charger tray includes a plate having a charger region and the plate is formed with one or more upstanding elements configured to keep the charger within the charger region. The charger tray's plate can also include at least one adapter-receiving region distinct from the charger region, and the charger tray's plate can be formed with one or more upstanding elements configured to keep a power cord adapter within the adapter-receiving region.
The shield can be constructed so that the first-mention container element and the additional container element are provided by a pouch having first and second openings, and the housing can further comprise a rigid device tray and a rigid charger tray. The device tray is sized for insertion in the pouch's first opening and includes a plate and an upstanding frame whose inner dimensions define the opening for the first-mentioned container element. The charger tray is sized for insertion in the pouch's second opening and includes a plate formed with one or more upstanding elements configured to constrain the charger.
In any of the embodiments discussed above, the first shielding material can be formed as a layer inside the first housing portion and include a portion that surrounds the opening in the first housing portion. The closure element can be formed as a flap that extends from the container portion, with the flap having a proximal portion formed adjacent the opening and a distal portion. In such a configuration, the engagement position is a folded position where the flap's proximal portion extends across the opening, and the second shielding material is formed on the flap's proximal portion. The non-engagement position is a folded position where the flap's proximal portion extends away from the opening so that the second shielding material is held away from the opening and does not contact the first shielding material.
In configurations having an additional open-ended container portion, the shield can further include a battery charging device held inside the additional container portion. In any of the embodiments discussed above, the first shielding material and/or the second shielding material can have at least a portion formed as a metallic (e.g., copper) mesh or as a metallized film or fabric.
In another aspect of the invention, a shield for a portable electronic device comprises a pouch, a rigid device tray, a rigid charger tray, first shielding material, and second shielding material. The pouch includes a set of outside walls that define an inner volume with an open end, an internal wall that divides the inner volume into first and second compartments and defines first and second openings at the pouch's open end, and a flap. The flap is connected to at least one of the outside walls, and is selectively movable between an open position that exposes the first and second openings and a closed position that closes the pouch.
The device tray is sized for insertion in the pouch's first opening and includes a plate and an upstanding frame whose inner dimensions are sized to accommodate the portable device. The charger tray is sized for insertion in the pouch's second opening and includes a plate having a charger region and at least one adapter-receiving region distinct from the charger region, one or more upstanding elements configured to accommodate a charger and to keep the charger within the charger region, and one or more upstanding elements configured to keep a power cord adapter within the adapter-receiving region.
The first shielding material is located inside the first compartment for partially surrounding the portable device when the portable device is inserted into the first compartment, and the second shielding is material mounted to the flap. When the flap is in its closed position, the first shielding material and the second shielding material together substantially surround the device, thereby substantially preventing RF signals emitted by the device from leaving the shield, and further substantially preventing RF signals impinging on the shield from outside from reaching the device. When the closure element is in its open position, the first shielding material and the second shielding material leave a gap, thereby allowing RF signals emitted by the device to leave the shield, and further allowing RF signals impinging on the shield from outside to reach the device.
A further understanding of the nature and advantages of the present invention may be realized by reference to the remaining portions of the specification and the drawings, which are intended to be exemplary and not limiting.